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Parents are right: children with autism experience more GI symptoms

By Kelly Lenox

Hertz-Picciotto, lead researcher on the study, also launched the
CHARGE study, the first large, comprehensive population-based study of environmental factors in autism, and the landmark
MARBLES study of early environmental and biologic predictors of autism.
(Photo courtesy of UC Regents)

“GI problems may create behavior problems, and those behavior problems may create or exacerbate GI problems,” noted Virginia Chaidez, Ph.D., a postdoctoral researcher at UCD at the time of the study. “One way to try to tease this out would be to begin investigating the effects of various treatments and their effects on both GI symptoms and problem behaviors.”
(Photo courtesy of UC Regents)

Researchers at the University of California, Davis (UCD), have found that young children with autism spectrum disorder (ASD) and developmental delays are at least three times more likely to experience frequent gastrointestinal (GI) problems than are typically developing children.

The
study findings appeared in the November 2013 issue of the Journal of Autism and Developmental Disorders.

Parents of children with ASD reported frequent occurrence of certain GI symptoms, including diarrhea, constipation, and sensitivity to foods, six to eight times more often than do parents of typically developing children. Furthermore, among all children with ASD, the presence of GI symptoms was associated with behaviors such as irritability, social withdrawal, and hyperactivity.

Results parallel parent reports

“After years of parents raising concerns about such symptoms, the huge differences we see … put to rest the idea that gastrointestinal problems among children with autism spectrum disorder are just an accumulation of case reports,” observed
Irva Hertz-Picciotto, Ph.D., lead researcher on the study.

Linked Video

Named one of the 2013
Top 10 Advances in Autism Research by Autism Speaks, the study is notable for its involvement of a large, ethnically diverse population. Researchers enrolled nearly 1,000 children, aged 24-60 months, approximately one-half of whom were white, one-third Hispanic, and one-sixth from other racial and ethnic backgrounds.

Determining causality requires further study

Researchers note that, although mechanisms and contributing factors explaining the differences they found are not yet understood, a chronic problem causing pain, discomfort, or anxiety could plausibly contribute to increased irritability and social withdrawal, especially in a person with deficits in social and communicative skills. Also, because neurotransmitter systems that are active in the brain also function in the gut, further research into GI symptoms could provide insight into neurobiological aspects of the disorder.

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